The invention relates to an electrical breaking device with multiple contacts, particularly suitable for a low voltage multipole circuit breaker at high currents.
Traditionally, a breaking device comprises a movable contact assembly and a stationary contact assembly. With the aim of reducing the contact resistance and improving the electrodynamic withstand at the level of the contact parts, it is state-of-the-art to use a breaking device with multiple contacts. U.S. Pat. No. 5,210,385 describes a multipole circuit breaker in which the movable contact assembly of a pole is provided with a plurality of contact fingers which extend parallel in a longitudinal direction and which are pivotally mounted around a transverse direction. One of the ends of each finger, the head, is provided with a movable contact part, whereas the other end of each finger, the heel, is connected by a flexible conductor to a common stationary contact pad. The stationary contact assembly of each pole is provided with stationary contact parts, designed to cooperate, in the closed position, with the movable contact parts.
It is also state-of-the-art, for example according to U.S. Pat. No. 3,154,662 and German Patent Application No. 1,107,330, to make use of the electrodynamic forces developed at the level of the movable parts of a breaking device.
The object of the invention is to improve the electrodynamic withstand at the level of the contact parts, without however increasing the number of contact fingers. To this end, it makes use of the electrodynamic forces developed at the level of the contact fingers.